The Journal of the British Astronomical Association

Volume 115, No.1: 2005 February

On this page: Notes and News / Articles / Observers' Forum / Reviews / Meetings / BAA Update

On the cover: An infrared view of the Orion nebula

The first light image for the Wide Field Camera (WFCAM) recently erected on the UK Infrared Telescope (UKIRT) on Hawaii. Built at the UK Astronomy Technology Centre (UK ATC), Edinburgh, at half a degree across WFCAM has the largest field of view of any astronomical infrared camera in the world. As part of its commissioning programme WFCAM imaged a region of star formation in Orion. Joint Astronomy Center, Hawaii. .

Notes and News

From the President (Tom Boles) / SMART I - a slow probe to Luna (Roger O'Brien) / Solar Section (Mike Beales) / Aurora Section (Ron Livesey) / The Fourth European Dark-Sky Symposium, Paris (Bob Mizon) / Venus at western elongation, 2004 (Richard McKim) / Huygens begins its final journey (Hazel McGee) / More stunning images from Cassini (John H. Rogers) / Deep Sky Section meeting 2005 (Stewart Moore)

Cassini captured Saturn's moon Dione against the globe of the planet as it approached the icy moon for its close rendezvous on 2004 Dec 14. This natural colour view shows the moon has strong variations in brightness across its surface, but a remarkable lack of colour, compared to the warm hues of Saturn's atmosphere. The images used to create this view were obtained with the Cassini wide-angle camera at a distance of approximately 603,000km from Dione. NASA/JPL/Space Science Institute.

Main articles

Henry McEwen of Glasgow: a forgotten astronomer? Part 1: Moray Firth to Mount Florida (1864-1916)... Richard McKim Even half a century after his death, few details have been published concerning the life and work of the Scottish amateur astronomer Henry McEwen (1864-1955). An engineer by training, he directed the BAA Mercury and Venus Section with distinction for the unprecedented span of 60 years (1895(1955). He was at one time President of the Association's West of Scotland Branch. Living in or near Glasgow for most of his adult life, he was geographically isolated from the bulk of the Association's members. He travelled to London only rarely.

Today, McEwen is nearly forgotten by those outside BAA circles. In this paper to commemorate the 50th anniversary of his passing, a detailed sketch of McEwen's astronomical labours is given in order to seek greater recognition for his work, and many new details of his life and family background are presented. He carried out important early mapping of the planet Mercury, considering (essentially correctly) that the bright areas of the planet might correspond to lunar-like rayed craters, recorded unusual cloud features on Venus, carried out valuable micrometrical work for Venus, and even compiled a tentative map of the planet. He also contributed to knowledge of the geological history of the Moon.
It is suggested that McEwen's astronomical work should be commemorated by having a feature on the planet Mercury named after him. (12pp)

Detection and measurement in the V-band of the white dwarf spin period in the January 2004 outburst of DO (YY) Draconis ... David Boyd

A modulation in the V-band with period 527.84±1.81 sec and amplitude 0.023 magnitude, attributable to the spin of the magnetic white dwarf primary star, has been detected in 7.5 hours of V-band CCD photometry data recorded during the January 2004 outburst of the DQ Her type dwarf nova DO (YY) Draconis. This measurement is consistent with previous results for the white dwarf spin period based on X-ray and UV observations made with the Hubble Space Telescope, ROSAT and the Rossi X-ray Timing Explorer and appears to be the first independent determination of the spin period in the V-band. It is consistent with previous V-band observations in not showing a significant signal at the first harmonic of the spin period as seen in X-ray and UV data. Light output in the V-band peaks only once per rotation of the white dwarf rather than twice as seen in X-rays and UV. Concurrent observation at optical and X-ray wavelengths is needed to establish whether these two modulation behaviours occur at the same time during the outburst and to investigate the phase relationship between them. A coordinated observing campaign at a future outburst would help to advance our understanding of this system. (4pp)

Neolithic and Early Bronze Age skywatchers and the precession of the equinox ... David W. Hughes

Skywatchers some 4500 years ago were seeking chronological determinants, such as the time of the summer solstice, using little mathematical knowledge. We investigate how accurately they could determine the solstice, and whether, in doing this, they should have discovered the precession of the equinoxes. (7pp)

A comparison of sunspot activity, geomagnetic activity, and the frequency of discrete auroral apparitions observed from the UK in the years 1977-2002 ... R. J. Livesey

The comparisons are presented in the form of eight graphs in the accompanying figure, giving annual values to a common time base. The paper also discusses magnetic and visual detection of activity and its solar origins. Sunspot cycle 23 has shown odd features in the distribution of activity. (3pp)

Observing near-Earth asteroids ... Roger Dymock

I explain to potential asteroid observers how they might progress from visual observing to CCD astrometry and photometry. The presentation covers my own experiences observing main belt asteroids and imaging near Earth asteroids. This presentation can be viewed in its entirety on my Near Earth Asteroid (NEA) website. Links to the sites mentioned in this article and a fuller explanation of the methods described here can also be found on this website.

Index to the Journal, 2004 ... R. J. Marriott

(Copies of any of these articles may be ordered from the BAA office.)

Reviews

(Here is an easy way to obtain your astronomy books, and help the BAA at the same time. Any books or other goods, including videos, computer software and music, ordered from Amazon after following a link from this site - not just books reviewed here - will generate a small commission for the BAA.)

Introduction to comets by by John C. Brandt & Robert D. Chapman
Cambridge University Press, 2004. Pp viii + 441. ISBN 0-521-80863-4, Ł75.00 (hbk); ISBN 0-521-00466-7, Ł35.00 (pbk).

Reviewed by Nick James